Task Manager and log off screens (XP PRO SP1)

Howdy,
I had to reinstall windows and now when I hit the Ctl Alt Del the screen is different. It's a box with different options instead of the Task Manager. Also when shutting down, I receive "Are you sure you want to log off?" whereas before I had a different screen--restart, log off, shut down. Is there a way to revert to my previous screens?
Thanks